Malicious PDF — malware analysis report

Static analysis result for SHA-256 198d25c2e10b9b92…

MALICIOUS

PDF

38.6 KB Created: 2020-08-07 23:32:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d5b064dcdcd6712973eb64183a1dfe29 SHA-1: 917af7ffffd681604a3026f2eae77468982d8ae1 SHA-256: 198d25c2e10b9b92bfc8586c43b787b0c30f515898fc9023199127b0987583c5
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a large number of embedded links, many of which point to external PDF files, suggesting a link farm or SEO poisoning attempt. The primary malicious URL, https://ttraff.ru/pify?keyword=bsc+chemistry+question+papers+2020+pdf, is identified as a redirector to malicious infrastructure. The document body, though heavily obfuscated, contains references to academic papers and the malicious URL, reinforcing the lure.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://ttraff.ru/pify?keyword=bsc+chemistry+question+papers+2020+pdf
    • http://files.sjcacademy.com/uploads/1/3/0/7/130740142/df8fa.pdf
    • http://files.hdskiandmanagement.com/uploads/1/3/1/1/131164488/lodabaj-zoxufiputilo.pdf
    • http://files.researchingthewest.com/uploads/1/3/2/8/132814989/212562a5021.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0430/6688/4250/files/3276220707.pdf
    • https://cdn.shopify.com/s/files/1/0432/8259/6000/files/8847392853.pdf
    • https://cdn.shopify.com/s/files/1/0429/7061/1861/files/23461286793.pdf
    • https://cdn.shopify.com/s/files/1/0428/0962/2691/files/53998259403.pdf
    • https://cdn.shopify.com/s/files/1/0429/6340/2905/files/22539329221.pdf
    • https://cdn.shopify.com/s/files/1/0432/6214/8763/files/861610451.pdf
    • https://cdn.shopify.com/s/files/1/0431/8950/2110/files/jalatuvinunawifebutim.pdf
    • https://cdn.shopify.com/s/files/1/0430/3280/5527/files/88751313845.pdf
    • https://cdn.shopify.com/s/files/1/0432/7168/4252/files/fitekebasapegene.pdf
    • https://cdn.shopify.com/s/files/1/0431/6862/8890/files/nizezinukonapexeramudox.pdf
    • https://cdn.shopify.com/s/files/1/0429/2732/5343/files/91772188755.pdf
    • https://cdn.shopify.com/s/files/1/0435/1338/1028/files/95486437607.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000057cf.bin
93d40529ae2643d6b939e3dd85d40aa31398f61138e54ac25b6c1e002caf401d
pdf-font-stream PDF embedded font (sfnt) at offset 0x57CF 5912 bytes
font_01_sfnt_off00006bd0.bin
7f1a274bcc42393267cef762f1815296c62f9b35fc195860c9ebcf9865d2788c
pdf-font-stream PDF embedded font (sfnt) at offset 0x6BD0 9892 bytes